The present invention relates to flooring systems especially designed for facilities that house data processing equipment such as data processing centers, computer rooms, and offices where there is a false floor raised above the existing floor. Such false floors or raised panel floors typically utilize removable panels laid side-by-side upon raised support members in order to afford a free space where conduit, cables, hoses, wires and other computer interconnections can be routed. Many false flooring systems exist, including ones that use adjustable jacks at each panel corner as a means of support. The support jacks for such systems are only located at the corners of the panels, which are usually square with sides of 500 to 600 mm. Accordingly, rigidity and mechanical stability of the floor must be achieved through the use of very thick panels, usually 30 to 40 mm thick, sometimes including a framework which transfers the load to the jacks. Due to the loss of usable height, these types of false flooring require an overall height of 150 to 200 mm, which is incompatible with low ceilings in existing buildings and requires new facilities to be built with added height. As an example, if one considers a 200 mm false floor at each level of a thirty-story building, the additional required height becomes six meters, the equivalent of two stories. Installing such a false floor in existing buildings requires the construction of ramps and steps as well as fire and soundproofing barriers. Finally, such structures are sometimes noisy and act as resonators. In any event, installing existing false floors either as part of a building renovation or in new construction, is both involved and costly.
U.S. Pat. No. 5,052,157 (the "'157 patent"), incorporated herein in its entirety by this reference, describes an excellent "Flooring System Especially Designed for Facilities Which House Data Processing Equipment." The system described in the '157 patent solves many of the problems associated with previous systems, including such problems described above. However, the '157 patent contemplates and illustrates construction of portions of the system "by heat forming or injection molding of a plastic compound such as polystyrene, polyethylene, polypropylene or ABS." While such materials are excellent choices for the formation of the components for which they are suggested in the '157 patent, particularly in view of the complex shapes of some of those components, drawbacks are associated with the use of such materials in certain applications. First, the load-bearing capacity of a raised panel flooring structure utilizing such plastic materials is, in part, a function of the quantity and type of plastic materials utilized, and it can be difficult to achieve high load-bearing capacities with such plastic structures at acceptable costs and without undesirable weight. Additionally, although the nature of the application and the use of flame-retardant and smoke-suppression formulations and additives can make use of such plastic materials acceptably safe as construction materials, some fire codes nevertheless limit or prevent the use of plastic structures as components of raised panel flooring.
Use of metal in structures of raised panel flooring provides a logical alternative, noncombustible material. Indeed, the '157 patent suggests that the one-piece base plate and stand-offs structure described therein could be stamped from sheet metal and that the base plate in the separate base plate and stand-off embodiment of the invention could be thin galvanized sheet steel. The '157 patent does not, however, teach how to form any of the base plate or stand-off components described in it from metal. Moreover, stamping the one-piece base plate and stand-offs structure of the '157 patent from sheet metal is probably impractical because of the distance that metal would have to be drawn in order to form the stand-off structure. Formation of the separate stand-off structure taught by the '157 patent would encounter similar problems, and the patent does not even explicitly suggest the use of metal for that structure but rather teaches that "[t]hese stand-offs can be made of any material, but injection molded ABS would be advantageous." Separate metal stand-offs having the solid-surface, hollow truncated conical structure of the stand-offs taught in the '157 patent would also be difficult to attach to base plates because of the difficulty of deforming the stand-off in order to align or adjust attaching tabs or other members to achieve engagement with the base plate.
Numerous other prior raised panel or false floor systems use metal components, but many such systems also use combustible materials or are expensive, difficult to install, perform poorly, elevate the floor excessively, will not adequately accommodate conduit or other materials that need to pass under the raised floor, or have other drawbacks. Accordingly, there remains a need for a low profile raised panel flooring system using components compatible with the strictest fire codes, that can offer high load-bearing capacity and overcomes other disadvantages of the prior systems.